Fuel injector for fluid pumps for internal combustion engines



July 4, 1961 L. SHELTON 2,991,056

FUEL INJECTOR FOR FLUID PUMPS FOR INTERNAL COMBUSTION ENGINES Filed Sept24 1958 INVENTOR.

Lwfiefl L. 5/72/98 BY I ATTOENEK United States Patent r 2,991,056 FUELINJECTORFOR FLUID PUMPS FOR INTERNAL COMBUSTION ENGINES Luther L.Shelton, 101 E, 78th Terrace, Kansas City, Mo. Filed Sept. 24, 19 58,Ser. No. 763,149 3 Claims. (Cl. 261-50) This invention relates tointernal combustion engines and particularly to the fuel injector forthe fluid pumps of such engines.

The primary object of this invention is to provide a fuel injector forfluid pumps for internal combustion engines having structure capable ofcontrolling the flow of fuel in response to and in direct proportion tochanges in size of the throttle opening.

A further object of the present invention is the provision of a fuelinjector of the aforementioned character wherein is included valve meansassociated with the throttle of the engine in such fashion as tocompletely close the valve and prevent the flow of fuel when the engineis not running.

A yet further aim of this invention is to provide a fuel injector whichreceives and controls the flow of fuel from a pressurized tank and whichreceives air through an intake port of a size sufficient to supportcombustion when the engine is operating at maximum speed.

A still further object of this invention is to provide a fuel injectorwherein the fuel valve is mechanically operated in direct response toaction of the air intake valve.

Further objects will become apparent from the following specificationsreferring to the accompanying drawing wherein:

FIG. 1 is a fragmentary elevational view of a portion of an internalcombustion engine showing a fuel injector embodying the invention andoperatively associated with thefiuid pump thereof;

FIG. 2 is a side elevational view of the assembly shown in FIG. 1.

FIG. 3 is a fragmentary view of the linkage forming a part of thethrottle control;

FIG. 4 is an enlarged, fragmentary sectional view taken along line 44 ofFIG. 1;

FIG. 5 is a cross-sectional view taken on line 5--5 of FIG. 4; and

FIG. 6 is a plan view of the air valve plate.

The constant flow of fuel injection device hereinafter described is foruse with an internal combustion engine having a pump or similar meansfor delivering the fuel to the cylinders. The injector will not onlyassure a constant flow and the desired mixture of fuel, but will closethe fuel line completely when the engine is not in operation.

The fuel injection device is operably mounted on an air intaketube 10which communicates at its one end with a fluid pump 12 which pump 12feeds the mixture of fuel and air to the cylinder of the engine. Pump 12is of the type described in US. Letters Patent 2,948,230, issued to meon August 9, 1960, entitled, Fluid Pump, which pump requires no check orreed valves therein for controlling the flow of fluid therethrough, butprovides a means for permitting a continuous flow of fuel therethroughby virtue of the fact that the pumping action of the pump operates onboth sides of :a rotatable swash plate. By virtue of this constructionthe pump is interposed between the injection device and the cylinders ofan engine to increase the pressure of the fuel to facilitate moreeffective combustion within the cylinders while, at the same timemaintaining a continuous flow of fuel from said injection device to saidcylinders. Integral with straight, cylindrical tube 10 is boss 14 havinga longitudinal passage 16 therethrough coupled at one end with a fuelsupply line 18, which delivers fuel under pressure from a suitablypressurized fuel tank (not shown). The opposite end of passage 16communicates with tube 10, the opening into said tube 10 beingsurrounded by an inwardly extending, cylindrical, hollow sleeve 20having a plurality of radial perforations 22 therein whereby to placepassage 16 into communication with tube 10. Formed within sleeve 20 atthe lowermost portion thereof, and below the lowermost of perforations22 is a valve seat24, which cooperates with and receives a taperedshoulder 26 formed intermediate the ends of a longitudinallyreciprocable valve stem 28. Stem '28 fits loosely within sleeve 20 toallow fuel to pass therearound and into tube 10 through perforations 22when not seated. Stem 28 has an elongated shank 30, carried by acylindrical housing 32, surrounding shank 30'whereby to present -acontinuous, annular downwardly facing shoulder 34. Housing 32 is in turnreciprocably mounted within -a boss 36 formed on the outer surface oftube 10 at a point diametrically opposite boss '14. Housing 32 isinternally threaded, and shank 30 has cmplementary external threadswhereby shank 30 may be adjusted longitudinally within housing 32 whenrotated. Housing 32 is further provided with a longitudinal slot 38through the wall thereof and into Which slot pin 40-extends from a fixedposition in boss 36. Downward movement of housing 32 and shank 30 islimited by pin 40.

Housing 32 and shank 30 from which depends stem 28, are normally biaseddownwardly by a spring 42 surrounding housing 32, said spring 42 havingits lowermost end held in place by a collar 44 and its uppermost endabutting the interior surface of the wall of tube 10.

Extending through tube 10 and in intersecting relationship thereto is arotatable shaft 46. Afiixed to shaft 46, by screws 48, or other suitablemeans is a butterfly valve plate 50, of an area equal to and coextensivewith the cross sectional inner area of tube 10, whereby plate 50 mayentirely close said tube 10 and prevent the flow of air therethrough.

Butterfly valve plate '50 is provided with a notch 50 to accommodatesleeve 20 as plate 50 is rotated by shaft 46. Formed on one face ofplate 50 and projecting laterally therefrom is a pair of identical cams54, centrally disposed with respect to said face of plate 50. Cams 54are formed on the face of plate 50 opposite that to which shaft 46 isattached and a cam 54 is on each side of notch 52 as illustrated in FIG.6.

As shown in FIGS. 4 and 5 ofthe drawing, cams 54 are so positioned thatshoulder 34 is resiliently biased thereagainst by spring 42. When shaft'46 is rotated, plate 50 moves clockwise, viewing FIG. 4, and as suchmovement takes place, cams 54, acting against shoulder 34, move housing32, and valve stem 28 upwardly result-ing in moving shoulder 26 fromseat 24 to allow passage of fuel from line 18 into sleeve 20 and throughperforations 2 2 into tube 10 to be mixed with air entering tube 10 as aresult of the opening of plate 50. The mixture of fuel and air is thencarried into pump 12 and delivered to the cylinders of the engine.

As is evident from the foregoing, the fuel injector valve is directlyresponsive to the action of the air intake valve plate 50 and when saidplate is swung open to allow air to pass therebeyond a predeterminedamount of fuel is simultaneously allowed to enter tube 10. When plate 50is closed by the rotation of shaft 46 in the opposite direction fromthat opening plate 50, spring 42 acting against collar 44 moves shank 30and its associated valve stem 28 downwardly whereby shoulder 26 seatswithin seat 24 to prevent the passage of fuel into tube 10. To insurethat valve 28 is tightly closed when plate 50 is closed, said valve stem28 may be adjusted by shank 30. When valve-50 closed and the enginestopped, flow of fuel to tube is entirely shut 01f.

As best seen in FIGS. 1 and 2, shaft 46 is operated by suitable linkageconnecting the same to a throttle control. This linkage comprises amember56 pivotally supported as at 57 and suitably connected tooperating means (not shown) whereby member 56 may be swung tolongitudinally reciprocate an arm 58 which has at its uppermost end alink 60 coupling the same with one end of shaft 46. .1 When member 56 isswung in the direction of the arrow shown in FIG. 1, arm 58 and link 60rotate shaft 46 clockwise. (FIG. 4) to open valve 50. :1 Afiixed to: theopposite end of shaft 46 from that to which link 60 is coupled, isa-stop element 62. Adjacent element 62 but loosely mounted on shaft 46is an L- shaped lever 64 having a rod 68 pivotally connected to one legthereof. Rod 68 is coupled with a vacuum assembly 70 by having one endthereof directly connected to the flexible diaphragm 72 thereof. Vacuumassembly 70 communicates with tube 10 through a pipe 74 which opens intotube 10 at a point between valve 50 and pump 12 (FIG. 4).

The leg of lever 64 not connected to rod 68 is offset to place the freeend thereof in the plane of element 62. An adjusting screw 76 isthreaded through the offset end of lever 64 and abuts element 62 makingelement 62 responsive to the action of lever 64 when rod 68 is moved inone direction by vacuum assembly diaphragm 72. When rod 68 returns tothe position shown in FIG. 1, screw 76 serves to limit the clockwisemovement of element 62 and thus adjustably regulates the rotation ofshaft 46 and the closing of its associated fuel and air valves.

In operation shank 30 is adjusted so that shoulder 26, seating withinseat 24, closes fuel line 18 when the parts are in the positions shownin the drawing. As the starting of the internal combustion engine iscommenced a vacuum is created within tube 10, and more particularlyWithin pipe 74, causing diaphragm 72 to flex downwardly viewingFIG. 1.Such flexing of the diaphragm 72 exerts a downward pull on rod 68,rotating lever 64 about shaft 46 and moving screw 76 against element 62which is fixed to shaft 46. The movement of lever 64, and its adjustingscrew 76 against element 62, and the resulting rotation of shaft 46,causes air intake valve '50 to rotate and thus open the fuel valve apredetermined distance, allowing the necessary fuel and air mixture toreach the engine and insure starting. The distance which such valves areinitially allowed to open is controlled by the distance which diaphragm7'2 flexes downwardly and the adjustment of screw 76.

After the engine is started the air and fuel valves are operated bylinkage 56, 58, 60 which further rotate shaft 46, diaphragm 72 remainingfully downwardly flexed during such operation. When the engine isstopped and the vacuum through pipe 74 ceases, diaphragm 72 returns toits normal position, shown in FIG. 1, causing lever 64 to swing aboutshaft 46 and leave sufficient room for the rotation of element 62whereby shaft 46 may be rotated to such a position that stem 28 isbiased fully downwardly by spring 42 and completely closes fuel line 18as a result of shoulder 26 tightly engaging seat 24.

Having thus described the invention what is claimed as new and desiredto be secured by Letters Patent is:

1. In a fuel injector for a fluid pump for internal combustion engineshaving a pressurized fuel tank; an air intake tube for the pump; an airintake valve in the tube for controlling the passage of air through thelatter into the pump; cams integral with said valve; a fuel lineinterconnecting the fuel tank and the air intake tube; pressureresponsive means communicating with the tube; a fuel valve forcontrolling the flow of fuel from the line into the tube, said camsbeing in engagement with said fuel valve whereby said fuel valve isactuated by operation of said air intake valve, said air intake valvebeing operably coupled with said pressure responsive means whereby achange of pressure within the air intake tube will operate said airintake valve.

2. In a fuel injector for a fluid pump for internal combustion engineshaving a pressurized fuel tank; an air intake tube for the pump; an airintake valve in the tube; cams integral with said air intake valve; afuel line interconnecting the fuel tank and the air intake tube; a fuelvalve for controlling the flow of fuel from the line into the tube, saidcams being in engagement with said fuel valve whereby said fuel valve isresponsive to the action of said air intake valve; pressure responsivemeans communicating with the tube between said air intake valve and saidpump; and linkage operably coupling said means with said air intakevalve, whereby actuation of said means will operate said air intakevalve.

3. In a fuel injector for a fluid pump for internal combustionengineshaving a pressurized fuel tank; an air intake taube for the pump;an air intake valve in the tube; cams integral with said air intakevalve; a fuel line interconnecting the fuel tank and the air intaketube; a fuel valve for controlling the flow of fuel from the line intothe tube, said cams being in engagement with said fuel valve wherebysaid fuel valve is responsive to the action of said air intake valve; apressure responsive diaphragm; a pipe interconnecting said diaphragm andsaid tube, said pipe communicating with the tube between said air intakevalve and said pump; a rod operably coupled with said diaphragm; andadjustable linkage coupling said rod with said air intake valve wherebythe creation of a vacuum within said pipe will cause said air intakevalve and said fuel valve to open a predetermined distance.

References Cited in the file of this patent UNITED STATES PATENTS1,393,366 Henderson Oct. 11, 1921 1,773,290 Waite Aug. 19, 19301,991,804 Johnson Feb. 19, 1935 2,318,216 Garretson May 4, 19432,595,720 Snyder May 6, 1952 2,741,466 Udale Apr. 10, 1956

